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Numb (dumb?) Question: does this alloy make 'passable' bearings/bushings? As in "could I cast bushings with built-in mounting flanges, given suitable raw materials?"

Note that alteration of the mixture is acceptable, i.e. less zinc / lead and more tin. Note also that I'm not picky beyond 'it shouldn't be a complete headache to cast or machine, and work *passably* as a bearing, too.'

den, I took a quick look at some of Ammen's mixes and the closest to the 85 triple 5 is bearing bronze at 80 copper and 10 each of lead and zinc, or journal bronze with 82-84 copper, 12-14 silicon, 2-4.5 zinc and less than 1 of lead and iron.
I have no idea as to the ease of casting.

I'm pretty sure you could make and cast any bearing alloy you wanted. There may be a little porosity but that should not hurt a bearing at all. I have cast bronzes with Cu content ranging from 65-95%. I have used various alloying metals.
C932 bearing bronze is very close to what I made here:

One question you have to consider is the speed of the shaft in the bearing. Having been in the old time wooden boat building business when I was younger, I had to pour bearings for my machinery sometimes, most of which ran using wide flat belts on two inch shafts run at a fairly low speeds. Damn near any bronze or lead/tin alloy did fine for that. If you are running a small shaft at 3000 rpm, the requirements are more particular. You want a tin bronze with some lead in it, or a Babbitt metal with a lot of tin.

'Bearing', as in a hand-turned/twisted 1/2-10 acme thread turns in it (as a nut), as part of an ersatz right-angle welding clamp (which normally goes for $$$$, if one wants to buy store-bought ones. If one wants 'several' - in our case, eight of 'em for the group's use - the tariff could easily kill a k-bill, i.e. over a hundred PER item, gack!)

Note: main castings for the eight are done, and want machining time. The large mill is somewhat lacking in the clamping department, hence tooling needs making first!

Note 2: the current drawing showes a #60 drill hole for 'oil'.

Basically, I was 'after' a half-baked version of #660 bronze - half-baked as in 'he was using a lot of scrounged materials for the ingredients, and wasn't being especially careful about the formulation'. Then again, I doubt this is an arduous aplication...

Last edited by den; 04-29-2017 at 05:15 PM.
Reason: Original needed clarification